ipv4: expose IPV4_DEVCONF

IP sends device configuration (see inet_fill_link_af) as an array
in the netlink information, but the indices in that array are not
exposed to userspace through any current santized header file.

It was available back in 2.6.32 (in /usr/include/linux/sysctl.h)
but was broken by:
  commit 02291680
  Author: Eric W. Biederman <ebiederm@xmission.com>
  Date:   Sun Feb 14 03:25:51 2010 +0000

    net ipv4: Decouple ipv4 interface parameters from binary sysctl numbers

Eric was solving the sysctl problem but then the indices were re-exposed
by a later addition of devconf support for IPV4

  commit 9f0f7272
  Author: Thomas Graf <tgraf@infradead.org>
  Date:   Tue Nov 16 04:32:48 2010 +0000

    ipv4: AF_INET link address family

Putting them in /usr/include/linux/ip.h seemed the logical match
for the DEVCONF_ definitions for IPV6 in /usr/include/linux/ip6.h
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/inetdevice.h

@@ -5,45 +5,13 @@
 
 #include <linux/bitmap.h>
 #include <linux/if.h>
+#include <linux/ip.h>
 #include <linux/netdevice.h>
 #include <linux/rcupdate.h>
 #include <linux/timer.h>
 #include <linux/sysctl.h>
 #include <linux/rtnetlink.h>
 
-enum
-{
-	IPV4_DEVCONF_FORWARDING=1,
-	IPV4_DEVCONF_MC_FORWARDING,
-	IPV4_DEVCONF_PROXY_ARP,
-	IPV4_DEVCONF_ACCEPT_REDIRECTS,
-	IPV4_DEVCONF_SECURE_REDIRECTS,
-	IPV4_DEVCONF_SEND_REDIRECTS,
-	IPV4_DEVCONF_SHARED_MEDIA,
-	IPV4_DEVCONF_RP_FILTER,
-	IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE,
-	IPV4_DEVCONF_BOOTP_RELAY,
-	IPV4_DEVCONF_LOG_MARTIANS,
-	IPV4_DEVCONF_TAG,
-	IPV4_DEVCONF_ARPFILTER,
-	IPV4_DEVCONF_MEDIUM_ID,
-	IPV4_DEVCONF_NOXFRM,
-	IPV4_DEVCONF_NOPOLICY,
-	IPV4_DEVCONF_FORCE_IGMP_VERSION,
-	IPV4_DEVCONF_ARP_ANNOUNCE,
-	IPV4_DEVCONF_ARP_IGNORE,
-	IPV4_DEVCONF_PROMOTE_SECONDARIES,
-	IPV4_DEVCONF_ARP_ACCEPT,
-	IPV4_DEVCONF_ARP_NOTIFY,
-	IPV4_DEVCONF_ACCEPT_LOCAL,
-	IPV4_DEVCONF_SRC_VMARK,
-	IPV4_DEVCONF_PROXY_ARP_PVLAN,
-	IPV4_DEVCONF_ROUTE_LOCALNET,
-	__IPV4_DEVCONF_MAX
-};
-
-#define IPV4_DEVCONF_MAX (__IPV4_DEVCONF_MAX - 1)
-
 struct ipv4_devconf {
 	void	*sysctl;
 	int	data[IPV4_DEVCONF_MAX];

include/uapi/linux/ip.h

@@ -133,4 +133,38 @@ struct ip_beet_phdr {
 	__u8 reserved;
 };
 
+/* index values for the variables in ipv4_devconf */
+enum
+{
+	IPV4_DEVCONF_FORWARDING=1,
+	IPV4_DEVCONF_MC_FORWARDING,
+	IPV4_DEVCONF_PROXY_ARP,
+	IPV4_DEVCONF_ACCEPT_REDIRECTS,
+	IPV4_DEVCONF_SECURE_REDIRECTS,
+	IPV4_DEVCONF_SEND_REDIRECTS,
+	IPV4_DEVCONF_SHARED_MEDIA,
+	IPV4_DEVCONF_RP_FILTER,
+	IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE,
+	IPV4_DEVCONF_BOOTP_RELAY,
+	IPV4_DEVCONF_LOG_MARTIANS,
+	IPV4_DEVCONF_TAG,
+	IPV4_DEVCONF_ARPFILTER,
+	IPV4_DEVCONF_MEDIUM_ID,
+	IPV4_DEVCONF_NOXFRM,
+	IPV4_DEVCONF_NOPOLICY,
+	IPV4_DEVCONF_FORCE_IGMP_VERSION,
+	IPV4_DEVCONF_ARP_ANNOUNCE,
+	IPV4_DEVCONF_ARP_IGNORE,
+	IPV4_DEVCONF_PROMOTE_SECONDARIES,
+	IPV4_DEVCONF_ARP_ACCEPT,
+	IPV4_DEVCONF_ARP_NOTIFY,
+	IPV4_DEVCONF_ACCEPT_LOCAL,
+	IPV4_DEVCONF_SRC_VMARK,
+	IPV4_DEVCONF_PROXY_ARP_PVLAN,
+	IPV4_DEVCONF_ROUTE_LOCALNET,
+	__IPV4_DEVCONF_MAX
+};
+
+#define IPV4_DEVCONF_MAX (__IPV4_DEVCONF_MAX - 1)
+
 #endif /* _UAPI_LINUX_IP_H */